<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2016, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package    CodeIgniter
 * @author    EllisLab Dev Team
 * @copyright    Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright    Copyright (c) 2014 - 2016, British Columbia Institute of Technology (http://bcit.ca/)
 * @license    http://opensource.org/licenses/MIT	MIT License
 * @link    https://codeigniter.com
 * @since    Version 1.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * CodeIgniter Text Helpers
 *
 * @package        CodeIgniter
 * @subpackage    Helpers
 * @category    Helpers
 * @author        EllisLab Dev Team
 * @link        https://codeigniter.com/user_guide/helpers/text_helper.html
 */

// ------------------------------------------------------------------------

if (!function_exists('word_limiter')) {
    /**
     * Word Limiter
     *
     * Limits a string to X number of words.
     *
     * @param    string
     * @param    int
     * @param    string    the end character. Usually an ellipsis
     * @return    string
     */
    function word_limiter($str, $limit = 100, $end_char = '&#8230;')
    {
        if (trim($str) === '') {
            return $str;
        }

        preg_match('/^\s*+(?:\S++\s*+){1,' . (int)$limit . '}/', $str, $matches);

        if (strlen($str) === strlen($matches[0])) {
            $end_char = '';
        }

        return rtrim($matches[0]) . $end_char;
    }
}

// ------------------------------------------------------------------------

if (!function_exists('character_limiter')) {
    /**
     * Character Limiter
     *
     * Limits the string based on the character count.  Preserves complete words
     * so the character count may not be exactly as specified.
     *
     * @param    string
     * @param    int
     * @param    string    the end character. Usually an ellipsis
     * @return    string
     */
    function character_limiter($str, $n = 500, $end_char = '&#8230;')
    {
        if (mb_strlen($str) < $n) {
            return $str;
        }

        // a bit complicated, but faster than preg_replace with \s+
        $str = preg_replace('/ {2,}/', ' ', str_replace(array("\r", "\n", "\t", "\x0B", "\x0C"), ' ', $str));

        if (mb_strlen($str) <= $n) {
            return $str;
        }

        $out = '';
        foreach (explode(' ', trim($str)) as $val) {
            $out .= $val . ' ';

            if (mb_strlen($out) >= $n) {
                $out = trim($out);
                return (mb_strlen($out) === mb_strlen($str)) ? $out : $out . $end_char;
            }
        }
    }
}

// ------------------------------------------------------------------------

if (!function_exists('ascii_to_entities')) {
    /**
     * High ASCII to Entities
     *
     * Converts high ASCII text and MS Word special characters to character entities
     *
     * @param    string $str
     * @return    string
     */
    function ascii_to_entities($str)
    {
        $out = '';
        for ($i = 0, $s = strlen($str) - 1, $count = 1, $temp = array(); $i <= $s; $i++) {
            $ordinal = ord($str[$i]);

            if ($ordinal < 128) {
                /*
                    If the $temp array has a value but we have moved on, then it seems only
                    fair that we output that entity and restart $temp before continuing. -Paul
                */
                if (count($temp) === 1) {
                    $out .= '&#' . array_shift($temp) . ';';
                    $count = 1;
                }

                $out .= $str[$i];
            } else {
                if (count($temp) === 0) {
                    $count = ($ordinal < 224) ? 2 : 3;
                }

                $temp[] = $ordinal;

                if (count($temp) === $count) {
                    $number = ($count === 3)
                        ? (($temp[0] % 16) * 4096) + (($temp[1] % 64) * 64) + ($temp[2] % 64)
                        : (($temp[0] % 32) * 64) + ($temp[1] % 64);

                    $out .= '&#' . $number . ';';
                    $count = 1;
                    $temp = array();
                } // If this is the last iteration, just output whatever we have
                elseif ($i === $s) {
                    $out .= '&#' . implode(';', $temp) . ';';
                }
            }
        }

        return $out;
    }
}

// ------------------------------------------------------------------------

if (!function_exists('entities_to_ascii')) {
    /**
     * Entities to ASCII
     *
     * Converts character entities back to ASCII
     *
     * @param    string
     * @param    bool
     * @return    string
     */
    function entities_to_ascii($str, $all = TRUE)
    {
        if (preg_match_all('/\&#(\d+)\;/', $str, $matches)) {
            for ($i = 0, $s = count($matches[0]); $i < $s; $i++) {
                $digits = $matches[1][$i];
                $out = '';

                if ($digits < 128) {
                    $out .= chr($digits);

                } elseif ($digits < 2048) {
                    $out .= chr(192 + (($digits - ($digits % 64)) / 64)) . chr(128 + ($digits % 64));
                } else {
                    $out .= chr(224 + (($digits - ($digits % 4096)) / 4096))
                        . chr(128 + ((($digits % 4096) - ($digits % 64)) / 64))
                        . chr(128 + ($digits % 64));
                }

                $str = str_replace($matches[0][$i], $out, $str);
            }
        }

        if ($all) {
            return str_replace(
                array('&amp;', '&lt;', '&gt;', '&quot;', '&apos;', '&#45;'),
                array('&', '<', '>', '"', "'", '-'),
                $str
            );
        }

        return $str;
    }
}

// ------------------------------------------------------------------------

if (!function_exists('word_censor')) {
    /**
     * Word Censoring Function
     *
     * Supply a string and an array of disallowed words and any
     * matched words will be converted to #### or to the replacement
     * word you've submitted.
     *
     * @param    string    the text string
     * @param    string    the array of censored words
     * @param    string    the optional replacement value
     * @return    string
     */
    function word_censor($str, $censored, $replacement = '')
    {
        if (!is_array($censored)) {
            return $str;
        }

        $str = ' ' . $str . ' ';

        // \w, \b and a few others do not match on a unicode character
        // set for performance reasons. As a result words like über
        // will not match on a word boundary. Instead, we'll assume that
        // a bad word will be bookeneded by any of these characters.
        $delim = '[-_\'\"`(){}<>\[\]|!?@#%&,.:;^~*+=\/ 0-9\n\r\t]';

        foreach ($censored as $badword) {
            $badword = str_replace('\*', '\w*?', preg_quote($badword, '/'));
            if ($replacement !== '') {
                $str = preg_replace(
                    "/({$delim})(" . $badword . ")({$delim})/i",
                    "\\1{$replacement}\\3",
                    $str
                );
            } elseif (preg_match_all("/{$delim}(" . $badword . "){$delim}/i", $str, $matches, PREG_PATTERN_ORDER | PREG_OFFSET_CAPTURE)) {
                $matches = $matches[1];
                for ($i = count($matches) - 1; $i >= 0; $i--) {
                    $length = strlen($matches[$i][0]);
                    $str = substr_replace(
                        $str,
                        str_repeat('#', $length),
                        $matches[$i][1],
                        $length
                    );
                }
            }
        }

        return trim($str);
    }
}

// ------------------------------------------------------------------------

if (!function_exists('highlight_code')) {
    /**
     * Code Highlighter
     *
     * Colorizes code strings
     *
     * @param    string    the text string
     * @return    string
     */
    function highlight_code($str)
    {
        /* The highlight string function encodes and highlights
         * brackets so we need them to start raw.
         *
         * Also replace any existing PHP tags to temporary markers
         * so they don't accidentally break the string out of PHP,
         * and thus, thwart the highlighting.
         */
        $str = str_replace(
            array('&lt;', '&gt;', '<?', '?>', '<%', '%>', '\\', '</script>'),
            array('<', '>', 'phptagopen', 'phptagclose', 'asptagopen', 'asptagclose', 'backslashtmp', 'scriptclose'),
            $str
        );

        // The highlight_string function requires that the text be surrounded
        // by PHP tags, which we will remove later
        $str = highlight_string('<?php ' . $str . ' ?>', TRUE);

        // Remove our artificially added PHP, and the syntax highlighting that came with it
        $str = preg_replace(
            array(
                '/<span style="color: #([A-Z0-9]+)">&lt;\?php(&nbsp;| )/i',
                '/(<span style="color: #[A-Z0-9]+">.*?)\?&gt;<\/span>\n<\/span>\n<\/code>/is',
                '/<span style="color: #[A-Z0-9]+"\><\/span>/i'
            ),
            array(
                '<span style="color: #$1">',
                "$1</span>\n</span>\n</code>",
                ''
            ),
            $str
        );

        // Replace our markers back to PHP tags.
        return str_replace(
            array('phptagopen', 'phptagclose', 'asptagopen', 'asptagclose', 'backslashtmp', 'scriptclose'),
            array('&lt;?', '?&gt;', '&lt;%', '%&gt;', '\\', '&lt;/script&gt;'),
            $str
        );
    }
}

// ------------------------------------------------------------------------

if (!function_exists('highlight_phrase')) {
    /**
     * Phrase Highlighter
     *
     * Highlights a phrase within a text string
     *
     * @param    string $str the text string
     * @param    string $phrase the phrase you'd like to highlight
     * @param    string $tag_open the openging tag to precede the phrase with
     * @param    string $tag_close the closing tag to end the phrase with
     * @return    string
     */
    function highlight_phrase($str, $phrase, $tag_open = '<mark>', $tag_close = '</mark>')
    {
        return ($str !== '' && $phrase !== '')
            ? preg_replace('/(' . preg_quote($phrase, '/') . ')/i' . (UTF8_ENABLED ? 'u' : ''), $tag_open . '\\1' . $tag_close, $str)
            : $str;
    }
}

// ------------------------------------------------------------------------

if (!function_exists('convert_accented_characters')) {
    /**
     * Convert Accented Foreign Characters to ASCII
     *
     * @param    string $str Input string
     * @return    string
     */
    function convert_accented_characters($str)
    {
        static $array_from, $array_to;

        if (!is_array($array_from)) {
            if (file_exists(APPPATH . 'config/foreign_chars.php')) {
                include(APPPATH . 'config/foreign_chars.php');
            }

            if (file_exists(APPPATH . 'config/' . ENVIRONMENT . '/foreign_chars.php')) {
                include(APPPATH . 'config/' . ENVIRONMENT . '/foreign_chars.php');
            }

            if (empty($foreign_characters) OR !is_array($foreign_characters)) {
                $array_from = array();
                $array_to = array();

                return $str;
            }

            $array_from = array_keys($foreign_characters);
            $array_to = array_values($foreign_characters);
        }

        return preg_replace($array_from, $array_to, $str);
    }
}

// ------------------------------------------------------------------------

if (!function_exists('word_wrap')) {
    /**
     * Word Wrap
     *
     * Wraps text at the specified character. Maintains the integrity of words.
     * Anything placed between {unwrap}{/unwrap} will not be word wrapped, nor
     * will URLs.
     *
     * @param    string $str the text string
     * @param    int $charlim = 76    the number of characters to wrap at
     * @return    string
     */
    function word_wrap($str, $charlim = 76)
    {
        // Set the character limit
        is_numeric($charlim) OR $charlim = 76;

        // Reduce multiple spaces
        $str = preg_replace('| +|', ' ', $str);

        // Standardize newlines
        if (strpos($str, "\r") !== FALSE) {
            $str = str_replace(array("\r\n", "\r"), "\n", $str);
        }

        // If the current word is surrounded by {unwrap} tags we'll
        // strip the entire chunk and replace it with a marker.
        $unwrap = array();
        if (preg_match_all('|\{unwrap\}(.+?)\{/unwrap\}|s', $str, $matches)) {
            for ($i = 0, $c = count($matches[0]); $i < $c; $i++) {
                $unwrap[] = $matches[1][$i];
                $str = str_replace($matches[0][$i], '{{unwrapped' . $i . '}}', $str);
            }
        }

        // Use PHP's native function to do the initial wordwrap.
        // We set the cut flag to FALSE so that any individual words that are
        // too long get left alone. In the next step we'll deal with them.
        $str = wordwrap($str, $charlim, "\n", FALSE);

        // Split the string into individual lines of text and cycle through them
        $output = '';
        foreach (explode("\n", $str) as $line) {
            // Is the line within the allowed character count?
            // If so we'll join it to the output and continue
            if (mb_strlen($line) <= $charlim) {
                $output .= $line . "\n";
                continue;
            }

            $temp = '';
            while (mb_strlen($line) > $charlim) {
                // If the over-length word is a URL we won't wrap it
                if (preg_match('!\[url.+\]|://|www\.!', $line)) {
                    break;
                }

                // Trim the word down
                $temp .= mb_substr($line, 0, $charlim - 1);
                $line = mb_substr($line, $charlim - 1);
            }

            // If $temp contains data it means we had to split up an over-length
            // word into smaller chunks so we'll add it back to our current line
            if ($temp !== '') {
                $output .= $temp . "\n" . $line . "\n";
            } else {
                $output .= $line . "\n";
            }
        }

        // Put our markers back
        if (count($unwrap) > 0) {
            foreach ($unwrap as $key => $val) {
                $output = str_replace('{{unwrapped' . $key . '}}', $val, $output);
            }
        }

        return $output;
    }
}

// ------------------------------------------------------------------------

if (!function_exists('ellipsize')) {
    /**
     * Ellipsize String
     *
     * This function will strip tags from a string, split it at its max_length and ellipsize
     *
     * @param    string    string to ellipsize
     * @param    int    max length of string
     * @param    mixed    int (1|0) or float, .5, .2, etc for position to split
     * @param    string    ellipsis ; Default '...'
     * @return    string    ellipsized string
     */
    function ellipsize($str, $max_length, $position = 1, $ellipsis = '&hellip;')
    {
        // Strip tags
        $str = trim(strip_tags($str));

        // Is the string long enough to ellipsize?
        if (mb_strlen($str) <= $max_length) {
            return $str;
        }

        $beg = mb_substr($str, 0, floor($max_length * $position));
        $position = ($position > 1) ? 1 : $position;

        if ($position === 1) {
            $end = mb_substr($str, 0, -($max_length - mb_strlen($beg)));
        } else {
            $end = mb_substr($str, -($max_length - mb_strlen($beg)));
        }

        return $beg . $ellipsis . $end;
    }
}
